This is an example of; evolution
Evolution is a gradual process in which the characteristics of a species are changed in response to its environment over several generations. Evolution depends on the process of natural selection. Some of the changed characteristics (traits) may be beneficial to the organism and it can be transferred to their offspring.
The right answer for the question that is being asked and shown above is that: "D) The replacement of a native species of animal with an invasive species." The statement that describes an example of ecological succession is that The replacement of a native species of animal with an invasive species.<span>
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There is only 1 unique phenotype observed in the offspring. As all offspring produced would have the genotype of Aa. In which the characteristic for the dominant allele will be seen in all offspring. As all offspring are Aa. There is only 1 unique phenotype. Here based on the characteristic or phenotype expression of the dominant allele.
I believe the answer is different versions of a gene :)